Diana and Geoffrey have wealth but not happiness, his assistant Mark is carrying on with Diana, and the pair plot to kill Geoffrey. When Mark shoots him and goes the dispose of the body, he's gone, and a string of phone calls from beyond the grave begin.
I am a big fan of all things Francis Durbridge, and over the years his work has been adapted many times, Paul Temple and Melissa arguably the most famous works. Bat out of Hell is very typical of his style, with twists and turns galore. His work was popular all over the world. Surely it's time some of his books were remade.
John Thaw and Sylvia Syms are both particularly good, it's always nice e to see their early work. Thaw is loaded with charisma, Syms was very glamorous, and was always a fine actress.
Overall there is more than enough for whodunnit fans to keep them intrigued until the end, the red herrings do a good job in throwing you off the scent, maybe a bit slow for some, but overall I really enjoyed it.
7/10.